1. Field of the Invention
The present invention relates to a parallax correcting apparatus of a viewfinder which can be incorporated in a camera such as a compact camera using silver halide film, or a digital camera.
2. Description of the Related Art
In a manufacturing process for cameras such as compact cameras or digital cameras in which a photographing optical system and a viewfinder optical system are independent of each other, parallax correction is generally carried out to correct a difference between the image taken in by the viewfinder optical system and the image taken in by the photographing optical system, i.e., in order to correct a parallax occurring between the optical axis of the viewfinder and the optical axis of the photographing optical system.
As an example of a conventional parallax correcting apparatus, a parallax correcting apparatus in which the position (or angle) of at least one optical element among a plurality of optical elements (e.g., lens elements or mirrors), provided in a box-shaped hollow finder block, is constructed so as to be adjustable for parallax correction, is known in the art.
However, it is becoming increasingly difficult to adjust the position or angle of one or more adjustable optical elements in the finder block because the finder block, the adjustable optical element, and the camera which includes the finder block and the adjustable optical element, have been further miniaturized in recent years.
Due to such difficulty, for instance, the adjustable optical element and the finder block may come in contact with each other to thereby form scratches thereon during a parallax correcting operation.
Furthermore, foreign particles such as fine dust may enter into the finder block during the parallax correcting operation to thereby deteriorate the performance of the viewfinder.
The present invention provides a parallax correcting apparatus of a viewfinder, which is structured so that scratches are not made on either the finder block or the adjustable optical element in the finder block during the parallax correcting operation, and so that foreign particles such as dust do not enter into the finder block during a parallax correcting operation.
For example, a parallax correcting apparatus of a viewfinder of a camera is provided, including a finder block which accommodates all optical elements of the viewfinder; a stationary base which is integral with the camera body, the finder block being mounted on the stationary base; a pivotal projection and a pivotal recess which are formed on one and the other of the finder block and the stationary base, so that the finder block is rotatably engaged with the stationary base via the pivotal projection and the pivotal recess to allow the finder block to rotate relative to the stationary base, a common axis of the pivotal projection and the pivotal recess being perpendicular to an optical axis of the viewfinder; a first adjustment mechanism for rotating the finder block about the common axis; a pair of vertical position adjustment mounts formed on the stationary base on opposite sides of the common axis in a front and rear direction of the camera; a second adjustment mechanism for adjusting a height of one of the pair of vertical position adjustment mounts with respect to a height of the other of the pair of vertical position adjustment mounts which serves as a reference height; a pair of fixing mounts formed on the stationary base on opposite sides of the common axis in a right and left direction of the camera; and a pair of fixing limbs formed on the finder block which are fixed to the pair of fixing mounts, respectively, after the orientation of the finder block is adjusted via the first adjustment mechanism and the second adjustment mechanism.
The first adjustment mechanism can include an elongated hole formed on one of the pair of fixing limbs, the elongated hole being elongated in a radial direction from the common axis of the pivotal projection and the pivotal recess; a pivotal hole formed on the stationary base, the pivotal hole corresponding with the elongated hole; and an adjustment jig including a pivotal shank portion and an eccentric shank portion which are engaged in the pivotal hole and the elongated hole, respectively, an axis of the eccentric shank portion being eccentric to an axis of the pivotal shank portion.
One of the vertical position adjustment mounts can serve as a reference mount, and the other of the vertical position adjustment mounts can serve as an adjustment mount having a height smaller than a height of the reference mount. The second adjustment mechanism includes a plurality of spacers of different thicknesses, a spacer being selected from among the plurality of spacers to be inserted between the adjustment mount and the finder block.
The parallax adjusting mechanism can further include a pivotal mount formed on the stationary base, the pivotal recess being formed on the pivotal mount. Furthermore, the height of the reference mount is greater than that of the adjustment mount, the height of the adjustment mount is greater than that of each of the pair of fixing mounts, and the height of each of the pair of fixing mounts is greater than that of the pivotal mount.
It is desirable for the heights of the pair of fixing mounts to be the same.
The parallax adjusting mechanism can further include an adjustment jig support mount formed on the stationary base, wherein the pivotal hole, in which the pivotal shank portion of the adjustment jig is engaged, is formed on the adjustment jig support mount.
It is desirable for the heights of the pivotal mount and the adjustment jig support mount to be the same.
The pair of fixing limbs can be respectively fixed to the pair of fixing mounts by set screws.
The finder block can include a channel member and a top cover 15 which covers the top of the channel member, wherein the pivotal projection or the pivotal recess is formed on a bottom surface of the channel member.
The present disclosure relates to subject matter contained in Japanese Patent Applications No. 2001-162005 (filed on May 30, 2001) which is expressly incorporated herein by reference in its entirety.